Вай!
BT has a portfolio of granted patents and applications that relate to this area. Examples of BT’s patents include:
US PN 6,266,535 This patent is generally directed to the SIP REGISTER request that is used to associate SIP phones with IP PBXes and between IP PBXes and Internet Telephony Service Providers. This functionality is used in almost all SIP installations, including SIP Trunking as described in the SIPConnect specification.
Мы все это используем!
US PN 6,052,372 This patent is generally directed to translating a phone number into a contactable IP address for a gateway, which is a critical function that enables IP PBXes to place calls to conventional PSTN nodes. It is also applies to the use of peering gateways or session border controllers between enterprises and/or Internet Telephony Service Providers.
И это
US PN 6,407,996 This patent is generally directed to the way that SIP sets up calls using a proxy or call server to reach the destination. It is applicable to all SIP implementations that use a server for call routing.
US PN 6,765,886 This patent is generally directed to SIP call setup as typically used in SIP Trunking. It is about the use of a separate signaling and media paths, where calls may be set up or rejected using a proxy in a single SIP INVITE transaction. It applies to all SIPConnect complaint systems.
US PN 6,339,698 This patent is generally directed to reporting of call quality metrics by phones and gateways to a network management system. Most SIP Trunking implementations use such reporting functions, and they are required for typical SLA auditing.
US PN 7,197,030 This patent is generally directed to servers that track or limit the number of simultaneous calls to a given SIP trunk. It also applies to "forward on busy" services provided by the Internet Telephony Service Provider, as well as service continuity features that provide for default call handling when a SIP trunk is down and the PBX cannot be reached. SIP Trunking services commonly implement these functions.
Что говорить! Предлагаю начать сбор денег в пользу British Telecom.
